Control device



Jan. 16 1951 1, KETO 2,538,156

CONTROL DEVICE Filed April 22, 1946 WITNESSES: INVENTOR W fi fil/ywf ffeio.

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ATTORNEY Patented Jan. 16, 1951 UNITED STATES PATENT OFFICE CONTROL DEVICE August I. Keto, Sharon, Pa., assignor, by mesne assignments, to the United States of America; as represented by the Secretary of the Navy Application April: 22, 1946, Serial No. 663,897

control are such that the torpedo swings in normal running above and below the set or desired depth. This running may during transients, such as launching, be large enough that the torpedo broaches, thus revealing the general direction of the launching craft from the target.

One broad object of my invention is to provide an anticipating type of control to thus introduce movements of the elevator rudders in advance to the occurrence of depth variations greater than a given minimum.

A further object of my invention is the provision of means in the depth control for a torpedo that quickly and effectively damps out a, transient, such as is produced by launching, by anticipating rudder operation and reduces the deviation or swings in normal running above and below the set or desired depth to a small amount by anticipating the elevator rudder operation.

A more specific object of my invention is the provision of anticipating contact making devices for the control circuits of electromagnetically actuated elevator rudders.

Other objects and advantages will become more apparent from a study, of the following specification and the accompanying drawing in which:

The single figure is a schematic showing of my contribution to the art.

In the figure conductors l and 8 represent the positive and negative buses, respectively, connected to the torpedo battery, not shown. The connection of these buses to the torpedo. battery occurs during firing of the torpedo, or a predetermined time interval thereafter, depending on elements of control not forming part of my present invention.

The upper solenoid UE at the right controls the elevator rudders for the up-elevator position and the lower solenoid DE controls the elevator rudders for the down-elevator position. The relay 1, in conjunction with the depth control device D controls both, the solenoid UE and the solenoid DE.

The depth control device includes a pendulum 2 P pivoted at X to the removable support S secured in the top of the torpedo T, and to hydrostatic pressure responsive device H. The pendulum senses the swing in a vertical plane of the longitudinal axis of the torpedo with reference to the' horizon whereas the hydrostatic device senses the deviation of the torpedo from the set depth. The swing of the pendulum P with reference to the stops A and F on the torpedo body,

since the pendulum is coupled to the hydrostatic device, is a function of either deviation from the set depth of the torpedo below the sea surface, or the inclination of the longitudinal axis of the torpedo with reference to the horizon, or both. The showing in the figure is on the assumption that the aft end of the torpedo is to the right, whereas the forward end is toward the left.

Assuming the torpedo has been launchedconductors! and 8 are energizedthe torpedo is at the proper depth-for the moment the torpedo is operating with its longitudinal axis directed tothe left and at rated speedand the axis is at the normal or required aspect angle. Under these: conditions the contact d secured to the pendulum P hovers near contact 3. the torpedo takes an up-nose position greater than the normal aspect angle, that is, the torpedo is assumed to be swinging in the direction of an up-nose position, then contacts 3 and E engage.

This action establishes a circuit from the positive conductor 1- through conductor 2, contacts 3. and 4, conductor 5, actuating coil 6 of the relay 1 to the negative "conductor 8. Operation of this. relay causes the closing of contacts 9, to thus energize the down-elevator solenoid DE, and the opening of contacts It to deenergize the upelevator solenoid UE. The elevator rudders are thus thrown to a down position to counteract the up-nose swing of the torpedo. The counteracting force will continue as long as the swing is in the up-nose direction, assuming, of course, that the torpedo depth is correct and that at the moment only the normal running swings are involved. a

If the torpedo is at a depth that is too great then the hydrostatic eiiect of the depth control device will predominate and the rudders will be in the up-position', that is, solenoid UE will remain energized to thus steer the torpedo to the set depth level.

Since the contact 3 is mounted on the leaf spring I!) to which the piston I2 is attached the contact 3 will be moved aft, again assuming only the normal swings at the set depth. The piston l2 and cylinder H comprise a pneumatic dashpot. The leakage past the piston, or through a suitable adjustable orifice in the cylinder, or piston, provides for the desired function presently to be described.

After the torpedo has passed its maximum up-nose position and is swinging in the downnose direction, but is actually in an up-nose position, the dash-pot arrangement prevents contact 3 from following contact 4. The result is that the circuit for coil 6 is broken at contacts 3 and 4. Relay 7 is deenergized so that contacts 9 are opened and contacts I3 are closed.

The up elevator solenoid UE is thus energized to throw the elevator rudders to an up elevator position while the torpedo is still in an up-nose position but swinging to a down-nose position. The rudder action thus occurs in advance of the torpedo position by an advance phase angle. Since the swing amplitude is not of a fixed magnitude the value of the advance phase angle, within the limits set by the stops F and A, is a function of the swing amplitude.

As the torpedo swings to the extreme downnose position the Z-shaped bracket I4 of insulating material carried by the pendulum moves the contact 3 forward so as to move the piston I 2 forward in the cylinder H.

After the torpedo has swung past its maximum down-nose position and is Swinging in the upnose direction, but is actually still in a'downnose position, the movement of the contact 3 in the aft direction is delayed and contacts 3 and 4 engage before the pendulum is in the normal neutral position. The result is that the solenoid DE isenergized in advance of the movement of the torpedo to the normal aspect angle in its wing to an up-nose position.

By the system described above the dash-pot scheme provides a phase advancing scheme that will give a large phase advance angle for large angular deviations of the torpedo and a lesser phase advance angle for small angular deviations of the torpedo.

This function is of particular importance during the transients caused during and immediately after launching. The torpedo swing is quite violent during this launching period. Since the advance phase angle action of the rudders is large during this period the damping effect is large with the result that the violent swings are quickly dampened out and the torpedo swing is thus quickly reduced to the normal swing.

At the normal running angular amplitude of the torpedo, the phase advance is small but is just enough to keep the torpedo at or very near the proper depth.

While I have shown but one embodiment of my invention, I do not wish to be limited to the exact showing made but wish to be limited only by the scope of the claim hereto appended.

5 I claim as my invention:

In the depth control for a torpedo, in combination, electromagnetic means, including an armature and solenoid, for actuating the elevator rudders of the torpedo to' an up-rudder position, second electromagnetic means, including an armature and solenoid, for actuating the elevator rudders of the torpedo to a down-rudder position, a pendulous member mounted on the torpedo so as to be free to swing in a vertical plane with reference to the torpedo, whereby the position of the pendulous member with reference to a neutral position is a measure of the amplitude of swing of the torpedo axis with reference to the horizon, a pair of energized electric termia two-position electromagnetic switch, an actuating coil for said switch, said two-position switch when in its deenergized position adapted to connect one of said electromagnetic means to said terminals and when in its energized position adapted to connect the other of said electromagnetic means to said terminals, switching means mounted on said pendulous member, contact means, an elongated element secured to the torpedo at one end and carrying said contact means at the free end for movement through a given arc, a time delay timer connected to the element and acting to delay the return movement of the free end of the element upon displacement of the free end thereof, to a greater extent than a quarter cycle of a complete period of swing of the torpedo, said'contact means when engaged by the switching means on the pendulous member being effective to connect the actuating coil of said two-position switch to said electric terminals.

AUGUST I. KETO.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date r 1,378,291" Sperry May 17, 1921 in 1,532,616 Winkley Apr. '1, 1925 1,570,542 Winkley Jan. 19, 1926 2,099,808 Havill Nov. 23, 1937 2,100,934 Berges Nov. 30, 1937 

